Lids and containers equipped with said lids are known, which are normally used for drinks, or in some cases containers of this type are also used to contain other things.
Said containers are normally substantially cylindrical but they can also have a substantially quadrangular section, extending along the axis perpendicular to said section.
Different experiences are known regarding lids of said known containers, where the delivery hole is obtained by pulling off a very small part of the lid, using a predefined breaking line present in the lid itself.
U.S. Pat. No. 3,731,836 describes a system for opening a closing stopper defined by a closed line of weakening of a can; in this solution, a gripper ring of a lever or tab serves to open the stopper and is located in a substantially central position. The lever has its rotation fulcrum in correspondence with the periphery of the upper wall of the can, whereas in an intermediate position between the gripper ring and the fulcrum there is a rivet type solidarization mean.
A flexible connection element is provided between the gripper ring and the lid of the can and the lever or tab acts on a portion of the can lid outside the closing stopper so that, in the first opening movement, the stopper is lifted and pulled upward and is made to rotate around a pin, with problems relating to time and safety both during the opening step and also when the container is used.
WO 01/02260 describes a system for opening a closing stopper defined by a closed line of weakening of a can, in which the lever or tab, with the relative gripper ring, has its fulcrum on the periphery of the can lid; the gripper ring is central and a rivet, between fulcrum and ring, attaches the opening lever or tab to the stopper.
In this case, since the fulcrum of the lever or tab is in correspondence with the line of weakening that defines the stopper of the can, the action of the lever or tab determines a thrust of the stopper toward the inside, for a first breaking of the line of weakening. Subsequently the lever or tab is used as a traction element to remove the stopper.
This system can put the content in contact with the outside of the tab.
Moreover, this is a system that is dangerous in use.
U.S. Pat. No. 5,145,086 describes a system for opening a closing stopper defined by an open line of weakening of a can, in which the gripper ring of the opening lever or tab is central; the lever or tab has a fulcrum in correspondence with the periphery of the can lid and a rivet is provided which connects the opening lever or tab to the stopper of the can.
The lever or tab acts on a portion of the can lid outside the closing stopper so that, in the first opening movement, the stopper is lifted and pulled upward and is not thrust inside the can.
This solution creates problems of safety for the user, both during opening and when the container is used.
U.S. Pat. No. 3,795,340 describes a system for opening a can in which the lever or tab has a peripheral fulcrum and a central gripper ring.
The stopper of the can occupies a large part of the upper wall thereof, and is defined by a closed and circular line of weakening which substantially coincides with the circumference of the can.
The lever or tab acts inside the closed and circular line of weakening so that, at a first opening movement, the stopper is thrust inside and subsequently is completely removed through traction.
This system too can put the content in contact with the outside of the tab.
Moreover, in this case too, this is a system that is dangerous in use.
U.S. Pat. No. 4,189,060 describes a system for opening a can in which the lever or tab is used to pull off the stopper of the can in a traditional way.
The gripper ring of the lever is normally in a central position; the relative fulcrum of the lever is peripheral.
The rotation of the lever does not cause, as in the prior art documents described above, a portion of the closing stopper to break, but only serves to dispose the lever in an operating position, which lever is then driven, causing the closing stopper to be pulled in correspondence with the protuberance of the aperture.
A connection element comprising a flexible part is provided to connect the lever to the can lid, also in the open position.
This system is not only complex, but also requires a considerable effort. It is also dangerous to use.
U.S. Pat. No. 3,386,613 has a fork-type lever in which the rivet is connected rotatably on a front segment of the lever. This teaching does not allow to obtain a focused point where the force to pull off the stopper can be applied. Furthermore, it provides a mechanical hinge which prevents any support of the front fulcrum in proximity with the start of breaking, since it does not allow to contain the length of the lever, making it difficult to start the breaking.
US 2007/0131693 has a line of breaking that develops along the periphery of the lid; moreover it is the tab which, with its front part, starts the breaking. Additionally, a part of the opening mechanism enters inside the container.
WO 03/010054 provides a tab that starts the opening from a position located inside the lid and extends it until the stopper is completely detached from the lid.
WO 00/58161 provides a stay-on tab in which the stopper penetrates inside the container.
The present invention, advantageously but not exclusively directed to characterize the lids of containers for drinks, has set itself the purpose of overcoming the limits of known solutions and of achieving a system that entails new and unexpected advantages.
Its purpose is also to improve and perfect the inventive idea set forth in WO 2009/030526.